Hydraulic air-compressor.



Patented Nov. |4, 1899.

no. 637,|44. L. E. MITCHELL.

HYDRAULIC AIR COMPRESSOR. (Application filed Har. 80, 1899.) (No Model.)

er l

Z7 JQ I )3f/aj .f l v 'f 6,-/ p

3 al I; g3 I 2 ,a l? j "D j 'I p* I l i f 1P In lfm" ff f I4 ll Z7 Jln/[HHH l\ Y ||||l i 1 if lf f41 *L42 L', m JW q U Ll Ll /NVENTUH W/TNE SSES A' TroH/VE YS.

ma Nnnms PETERS co., PHoTaLxTHo.. wAswNoToN, D. c

UNITED STATES PATENT OFFICE.

LEE EDWARD MITOHELL'OF BOSTON, MASSACHUSETTS.

HYDRAULIC AIR-COMPRESSOR.

SPECIFICATION forming part of Letters Patent No. 637,144, dated November14, 1899. Application filed March 30, 1899. Serial No. 711,117. (Nomodel.)

T0 all whom it may concern:

Be it known that I, LEE EDWARD MITCHELL, of Boston,in the county ofSuffolk and State of Massachusetts, have invented a new and ImprovedHydraulic Air-Compressor, of which the following is a full, clear, andexact description.

My invention relates to an improvement in devices for compressing air bythe use of water and comprises novel features, which will be hereinafterdescribed and claimed.

Reference is to be had to the accompanying drawings, forming a part ofthis speciiication, in which similar characters of reference indicatecorresponding parts in all the figures.

Figures 1 and 2 are sectional elevations of my device, -showing theparts in different positions, and Fig. 3 is a plan View of my devicewith the I'ioat and tank removed and with the central pipe and itssurrounding sleeve in section.

The object of my invention is to provide a device which shall beoperated by a iiow of water to compress air and which shall also besimple in construction and not likely to get out of order and refuse towork. The mechanism of the device is included within a tank A, whichacts as the cylinder within which the air is compressed. This cylinderis provided with a base C, to which the body of the tank is secured bymeans of iianges and bolts or by any other suitable means. This base ispreferably provided with legs C3, which will raise it a short-distanceabove the ioor and provide room for the passage of the water-pipes. fThe tank is also provided with a dome A of such size as to receive thefloat D3 and connected at its top with a pipe B, which contains acheck-valve B to prevent backflow of the air and to which pipe theairdelivery pipe is to be attached.

The base C is provided with a central aperture, and a tube D extendsupwardly into the dome, through which tube the air is introduced to thetank. The upper end of said tube is coned or otherwise formed toconstitute a valve-seat. Surrounding the upper end of the tube is asleeve E, which is provided with side openings e for the passage of airand has its upper end covered by a cap E', between which cap and the endof the tube is held a washer e', of rubber or similar material, whichwill form a valve. When the sleeve is down in the positiony shown inFig. 1, the opening at the upper end of the tube is closed, while whenthe sleeve is raised to the position shown in Fig. 2 air is free toenter the tank.

Surrounding the tube D is a second sleeve D', which at its lower endsupports a pan D2. This sleeve is also provided with two collars ol andd', located one near the middle of the tube and the other at its upperend. Between these two collars is placed the oat D3, which is held inplace by the collars, but is free to slide upon the sleeve within thelimits of the collars.

Placed eccentrically of the center of the base are two openings, throughwhich the water enters the tank and escapes therefrom. The water entersthrough a passage C2, which is preferably formed within a boss extendingdownward from the base C, and escapes through a passage C', formedsimilarly in a downward extension of the base. The opening C4, whichcommunicates with the passage C', opens directly into the tank and isthe outflow or discharge opening.

The passage C2 communicates with a pipe H', which extends upwardlywithin the tank and is connected at its upper end with ahorizontalpassage or pipe H. Within the pipe H, at its upper end, is placed acheck-valve h, which prevents backiow of water.v Supported on the outerend of the horizontal pipe H is a pipe F, within which is placed a valvecontrolling the admission of Water to the tank. This valve consists ofthe two disks G2 and G3, which closely fit the pipe and are slightlyseparated from each other, both being mounted upon a valve stem or rodG. This rod projects from both ends of the pipe F and is supported insuitable bearings at each end thereof. The lower end of the pipe F is atsome distance above the bottom of the tank and has free communicationwith lthe interior of of rubber or similar packing material, whichassures a tight joint where the water is admitted and forms a seat forthe valve G.

The pipe IVI is provided with an upward extension, which, as hereinshown, consists of a plug H3, screwed into the upper end of the pipe.This extension has a horizontal arm H3, within the end of which isformed a bearing receiving one end of a rock-shaft J. The other end ofthis rock-shaft is supported in the upper end of a standard I. Mountedupon this rock-shaft is a sleeve K, from which projects an arm K3, uponthe outer end of which is a counterweight K. This sleeve K also has twoarms L, projecting oppositely, one at each side of the sleeve D'. Thesearms are connected by means of links L with the collar d upon the sleeveD.

The shaft .I has secured thereto two collars O3, each of which isprovided with an arm havinga lateral extension engaging one of the armsL. The arm O, which extends from one of the collars, passes beneaththearm L, while the arm O passes above the arm L. These two arms O and Ooccupy different angular positions, so that they will not be engaged bythe arms L except at the ends of their swing. Secured to one end of therockshaft .I is an arm J3, which is connected with the upper end of thevalve-rod G, so that when the shaft J is rocked the valve consistingr ofthe disks G2 G3 will be raised or lowered.

The operation of my device is as follows: The valve G2 G3 is supposed tobe in its lowermost position, as shown in Fig. l. The device isconnected, through the passage C2, with a suitable source ofwater-supply. The water flowing through this passage passes thecheck-valve 7L and the valve G2 G3, flowing upwardly through the pipe Fand out into the tank. In this position of the valve G2 G3 thedischarge-valve G/ is closed. The tank will thus lill with water, whichwill rise above the pan D2, filling the same. As the water rises andnears the upper end of the tank it of course compresses the air withwhich the tank is filled and forces it by the check-valve B' as soon asthe pressure becomes greater than that on the other side of thecheck-valve. As the water rises the i'loat D3 is raised, engaging thecollar d' and carrying the sleeve D with it until it engages and raisesthe valvesleeve E. This lifts the valve e' and permits the air-pressureto blow off, thus relieving the water-discharge valve G of some of itspressure, so that the counterweight K is enabled to lift this valve andat the same time close the water-inlet valve G2 G3, thus cutting off theinilo Yvof water and opening the dischargevalve. In order to balance thedisk G3 aud cause it to move without having to overcome the pressure ofthe water, the second disk G3 has been provided. By this means thepressure of the water acts in both directions equally and does not causeany resistance to the motion of the valve. As the water is dischargedthrough the opening C4 the float D3 will drop until it rests upon thecollar d. The

weight of this float is, however, not suiiicient to overcome thecounterweight K when in its lowermost position. As the water continuesto fall it finally uncovers the pan D3, which is filled with water andis water-tight, so that the water cannot escape. This brings into effectan added weight, which is finally su'- cient to overcome the resistanceof the counterweight and to cause the sleeve D to drop. IVhen thisv isdone, the counterweight is thrown upward and the valve-rod, with itsattached valves, downward, thus closing the discharge-opening andopening the inflowopening.

The device is thus entirely automatic in its action and will continue aslong as the water is supplied.

Having thus fully described my invention, I claim as new and desire tosecure by Letters Patentl. A hydraulic air-compressor, comprising a tankhaving an air-discharge valve, an airinlet pipe extending upward withinthe tank and terminating in a valve-seat, a valve adapted to rest uponsaid seat and guided in vertical movement by said pipe, a sleevesurrounding said pipe and carrying at its upper end a float and at itslower end a water-pan, water inlet and discharge valves for the tank,connections for securing opposite action of said val ves, a rock-shafthaving a counterbalanceweight, and connections from the rock-shaft tothe water-controlling valves and the sleeve surrounding the air-inletpipe, substantially as described.

2. A hydraulic air-compressor, comprising a tank having air dischargeand inlet valves and a water-discharge opening in its bottom, a cylinderwithin the tank in line with said water-discharge opening and connectedwith a water-supply, a rod extending through said cylinder, and having awater-inlet valve and a water-exit valve thereon, a float connected withthe air-inlet valve to control it, and a counterbalanced rock-shaftconnected with the rod carrying the water-controlling valves and theair-inlet valve, substantially as described.

3. A hydraulic air-compressor, comprising a tank having air inlet anddischarge valves and water inlet and discharge valves, a rod connectedwith both water inlet and outlet valves to operate them, a rock-shafthaving an arm connected with said rod, a sleeve journaled upon therockshaft and having a counterweight and lever-arms connected therewith,bent arms carried .by the sleeve and eX- tending on opposite sides ofthe arm upon the rock-shaft, said bent arms being separated so as toengage the rock-shaft arms at the eX- tremities of their swing, and afloat connected with the lever-arms and adapted to overcome the counterweigh t, su bstantially as described.

LEE EDWARD MITCHELL.

Witnesses:

JAMES MCQUILLAN, R. H. BRADFORD.

IOO

IIO

